Middlings-purifier



(No Model.)

A. HUNTER.

V MIDDLINGS PURIPIER. o. 278,142. Patented May-22,1883.

Witnesses. fiz'veiztaif- N. PETERS. Finals-Lithographer. Withinglon, D. c.

UNITED STATES PATENT OFFICE.

ANDREW HUNTEaoF CHICAGO, ILLINOIS.

M-lDDLlNGS-PURIFIER.

SPECIFICATION forming part of Letters Patent No. 278,142, dated May 22, 1883.,

' Application filed April 19, 1880. (No model.)

To all whom it may concern Be it known that I, ANDREW HUNTER, of the city of Chicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in Middlings-Purifiers, which improvement is fully set forth in the accompanying drawings and specification.

In the drawings, Figure 1 is a side elevation of a middlings-purifier embodying my invention. Fig. 2 is a transverse vertical section of the shaker, showing a side view of the brush and friction-rolls.

The same letters of reference indicate the same or corresponding parts.

I do not deem it necessary to enter into the details of the working parts of the purifier which has heretofore been patented by me.

at is a receiving-hopper, into which the middlings are fed. m is a vibrating screen, covered with boltingcloth 0, for the purpose of sifting and grading the middlings. k k are rotary shafts. act are pulleys fitted or applied to said shafts. i i are belts for attaching the brush. 1) is a brush, with friction rollers h h fitted at each end by set-screws or bolts 3 d is a-blast-fan for producing a pressure under the silk. f is an exhaust-fan which operates in connection with the blast.

The operation of the parts now described is as follows: The middlings are fed into the hopper m and fall upon the vibrating frame m. The motion of the screen-frame causes the middlings to travel toward the tail. On account of the quantity offluft'y paste and cellulose, the cloth on top becomes pasted, which can only be removed by a brush traveling on its surface, assisted by a pressure-blast underneath and an exhaust above the screen. The brush traveling on top loosens the pasty material, the pressure from fan at raises it up, and it is caught by the suction and carried off. If a blast-fan only were used, the fluffy material would fall back and become incorporated with the middlings, which accounts for a large portion of fine purified middlings being soft and spongy. The treatment of middlings on a pnrifier screen with a traveling brush on top, a pressure-blast underneath, and a suction above,

produces a result not heretofore obtained. By the use of a brush and blast-fan alone, or a brush and suction fan alone, similar results cannot be obtained. The brush 1) travels on top of the screen-frame from the head to the tail in the same direction with the middlings but it is impossible to make both travel at the same speed. Consequently if the brush travels faster than the middlings, it piles them up in front of the brush and leaves a space behind the brush without any middlings, thereby affording a good opportunity for the pressureblast underneath to act on the loosened paste on the cloth. The brush b is fastened to belts 'i 'i. The belts pass around the pulleys a a, which are fastened to shafts 7c. The brush, when it travels from the tail to the head, leaves the cloth until it passes around the head-pulleys a a. The comparatively slow traveling of the brush 1) and the quick movement of the screen-frame cause the brush to act effectually. The brush b has friction-rolls h h, fastened at the ends by regulating screws 3 y. The friction-rolls travel on top of the sides of the screen-frame, thereby securing an even pressure on the cloth, which prevents the cloth from Wearing.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. The combination, in a middlings-purifier, of a screen, a brush arranged to travel over and operate upon the upper surface of said screen, and carrying-rolls mounted on the ends of said brush and adapted to travel upon the side bars of said screen, substantially as and for the purposes specified.

2. The combination, in a middlings-purifier, of a screen, a brush arranged to travel over and operate upon the upper surface of said screen, a blast-fan discharging under the screen, and a suction-fan above, substantially as and for the purposes specified.

ANDREW HUNTER. 

